Planetary Radio: Space Exploration, Astronomy and Science - Earth Shattering Impacts

Episode Date: January 6, 2003

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This is Planetary Radio. Hello again, everyone, and Happy New Year. I'm Matt Kaplan. This week on Planetary Radio, we'll talk with Adriana Ocampo. I'm Matt Kaplan. This week on Planetary Radio, we'll talk with Adriana Ocampo. Born in South America, educated in the U.S., and now a senior research scientist with the European Space Agency, Adriana will tell us about her work as a planetary geologist, particularly on the Earth-shattering effects of past asteroid impacts. Bruce Betts will be here, helping us to start the year with a look at what's up in tonight's sky and what to expect in 2003. First though, let's learn why the big planets get all the pretty rings on our new Q&A segment. I'll be back with Adriano Ocampo in just Hi, I'm Emily Lakdawalla with questions and answers.

A member from Halifax, Nova Scotia asked, Why do only the gas giants Jupiter, Saturn, Uranus, and Neptune have rings, while the rocky planets Mercury, Venus, Earth, Mars, and Pluto have none? We asked Larry Esposito, an expert on planetary rings and atmospheres at the University of Colorado, to answer this excellent question. Dr. Esposito explained that although planetary rings appear to be a solid disk, they are actually made of myriad small particles in orbit around the planet. These dusty rings are only found close to their parent body, where the planet's gravity is strong enough to overcome the particle's tendency to stick together and grow into a small moon. Planetary rings are transient. Ring particles are constantly being ground down

by collisions and swept away by frictional drag. Rings must be replenished by fresh supplies of dust knocked from small satellites. The balance between these acts of destruction and creation yields the rings we see today. Earth has no rings now, but it might have in its past. I'll explain about Earth's rings when I return in a few minutes. Now, back to Planetary Radio. Adriana Ocampo is on the phone with us now from Las Vegas, which is not usually where you spend time nowadays, except that you're home for the holidays, I guess. That's correct.

Yes, I'm visiting my parents and enjoying a wonderful holiday with my family. Now, if we had reached you about a week ago, you would have been where, in the Netherlands? That's correct. Currently, I'm working for the European Space Agency at ESTEC, which is located in Norveg in the Netherlands, at ESTEC, which is located in Norvac in the Netherlands, where ESA has the facility that constructs all their spacecraft. So NASA, JPL, now the European Space Agency.

You have come a long ways for someone who started out as a high school student who got a chance to work at JPL. Yes, yes. I think I've been extraordinarily fortunate to pursue my dreams as a young child dreaming about the stars and space exploration in Argentina. It was my dream to work at NASA and be able to explore the stars. And I find myself very fortunate to be able to have fulfilled that dream. How old were you when you moved to the United States, to California? I was about 14 years old.

And so you had already had this dream of working on space exploration for some time. Absolutely, absolutely. I was one of those dreamy childs. My parents always used to give me, you know, I was looking at the stars and I couldn't go to sleep without first going to the roof of the house in Argentina, in Buenos Aires, where I grew up, and looking at the stars and wondering what those point of bright lights were. So that was very much part of my childhood and my aspirations. And I take it nothing has changed your mind since those early days. Absolutely.

If anything, it's just been such a fantastic adventure to be able to study and explore that. I feel, as I mentioned, extraordinarily fortunate to be able to contribute a to contribute to the space exploration mission, not only as part of JPL, but as part of the National Aeronautics and Space Administration, and now with the European Space Agency. You have gotten around, and you have many areas of expertise, but I wonder if you might primarily think of yourself as a planetary scientist? Yes, indeed.

Actually, when I started in some ways going to school, as you mentioned, I started, I was fortunate to enter as part of the JPL Space Exploration Post that the Jet Propulsion Laboratory sponsors to this day still a group of explorers of the level of high schools that are able to pursue their aspirations and dreams in space exploration. And at that time, there wasn't a discipline of planetary science, really. exploration. And at that time, there wasn't a discipline of planetary science, really. But I was fortunate to work as part of the Viking mission, and I was hooked. When I first saw the first images of Mars as a young kid, I said, whoa, I need to learn more about that. And that's how planetary geology came to my life.

Well, let's talk about geology. Since you have not yet had the chance to walk among the rocks and hills of Mars, you have done a lot of interesting work on the subject of impacts, that is, big things and small things, of course, that have hit the Earth, doing varying degrees of damage and leaving varying degrees of evidence. Is that a fair description? Yes. Impact processes have played an extraordinarily important role on the formation not only of our planet, but the solar system.

I remember as an undergraduate here in Jinju, Jamaica,, speak to us on impact processes. And I was mesmerized, you know, by his extraordinary gift of inducing that, you know, wonder of adventure and wanting to learn more and how impact processes have played the important role in not only feeding life on our planet, perhaps, but as well as taking it away. And this is the question that, earlier by serendipity, I was able to come to study and do more researching, and the one of how impact creators brought the demise of life to our planet 65 million years ago. We had an extraordinary event that it was a great, really, portion of the Earth's history,

geological history. There was a tremendous enigma. What had happened 65 million years to bring about such a tremendous mass destruction or mass extinction in our planet in which over 50% of the living species at the time disappeared? And this was a tremendous enigma in geology. It hadn't been identified. There were several hypotheses. It turns out in 1980 when the Albert String father and son team published a paper in Science proposing that the reason the mass extinction

65 million years ago took place was due to the impact of a tremendous rock from space, an asteroid or a comet, and the key piece of evidence that they found was an element called iridium. Yes, the thin iridium layer that corresponded to that period 65 million years ago? Correct, yes. So this layer, you can go to any place on our planet, This layer, you can go to any place on our planet, and if you go to, you're able to find chronological datum or layer, geological layer,

you can find minute traces of this very rare element called iridium. And the key there is, although the earth's crust has iridium, but in tremendously small amounts, they found a larger concentration that did not correspond to the earth's grass iridium concentration. So they knew

that it had been enriched by something. So here they were with this conundrum. Okay, what could have brought this large concentration of this very rare element called iridium? There wasn't enough in the Earth's crust to produce this anomaly. And that's where they thought.

They knew the only other place that we could find large concentrations of iridium was in asteroids or comets. And that's when they proposed, they said, that there must have been a large rock from space that impacted the earth. Throwing up enormous, unimaginable amounts of dust and causing fires and huge amounts of smoke and basically cutting off the earth from the sunlight that kept its plants alive and since the plants kept everything else alive, that was the end for the dinosaurs and many other species? Yes, that's correct.

But one of the things that our team, our research team, contributed to as well, not only were we fortunate enough to finally find the impact, because that was the big story, where was the impact located? After the evidence of the paper that was published by the Albertson Science. Yeah, that was my next question. The impact was, but, you know, it was really trying to find out not only this amount of dust that it was distributing globally around the planet on Earth 65 million years ago. But really, what caused that long... The dust we know by modeling

is settled to the Earth's surface in about six months. So that wasn't long enough to really cause the species to go extinct. So we needed to identify a mechanism that was longer-term. And what we found here, a key component, was that the target rock where the asteroid or comet, this big rock from space hit,

was very rich in sulfur. And the sulfur was the key. The sulfur, after this massive explosion, basically melted away, evaporated, and formed sulfuric acid clouds that covered the planet and made it opaque for over 10 years. So that's what also broke the photosynthesis process and really was the long-term event that we were looking for.

And those were the ones that really cooled the planet. And you could see this recorded in the geological, by geochemical analysis, that the planet suffered a cooling right after 65 million years. And then very slowly, then it warmed up. So this once rather controversial theory is now pretty well accepted by the scientific community. Yes, correct. I think I had an extraordinary experience here with some part of the NASA delegation.

I had gone to Moscow. The Russians had treated the NASA delegation very nice and they treated us to go to see their Bolshevik ballet. And I had this young boy who sat next to me, and he needed to identify that I was a foreigner. So he wanted to practice his English. So he talked to me in his English, and we started a dialogue and asking him what was his favorite subject in school.

And he said, oh, I love dinosaurs, and I love paleontology and science, and he was so excited, he started telling me the whole theory of why the dinosaurs had gone extinct, and he knew what had happened and the asteroid impact in the Earth, and he knew about the iridium, and I said, my God, how wonderful. Here I am, you know, in the other end of the planet where the impact crater occurred. And the knowledge from this young boy, he has already captured and the knowledge

has already been taught in schools and has already spread. And I thought, well, this is the best evidence that science is working, you know, spreading the word and really advancing human knowledge. That's a wonderful story. We do need to take a break for a moment. If you can stay with us, Adriana,

and we hope that you will also stay with us for a little bit more of our conversation with research scientist, planetary scientist, now working for the European Space Agency, Adriana Ocampo. Planetary Radio will return in just a moment. This is Buzz Aldrin. When I walked on the moon, I knew it was just the beginning of humankind's great adventure in the solar system. That's why I'm a member of the Planetary Society, the world's largest space interest group. The Planetary Society is helping to explore Mars.

We're tracking near-Earth asteroids and comets. We sponsor the search for life on other worlds. And we're building the first-ever solar sail. You can learn about these adventures and exciting new discoveries from space exploration in The Planetary Report. The Planetary Report is the Society's full-color magazine. It's just one of many member benefits. You can learn more by calling 1-877-PLANETS. That's toll-free, 1-877-752-6387.

And you can catch up on space exploration news and developments at our exciting and informative website, planetarysociety.org. That's planetarysociety.org. The Planetary Society, exploring new worlds. planetarysociety.org. That's planetarysociety.org. The Planetary Society, exploring new worlds. Hello again, everyone. Matt Kaplan with Planetary Radio, and we are back with Adriana Ocampo, planetary scientist on the staff doing research for the European Space Agency.

Adriana, before the break, we were talking about how this once controversial theory of the great impact 65 million years ago is now pretty well accepted by the scientific community. You have continued your research in this area, though, and in fact, you've had some opportunities, more than one, I believe, to allow other people to become involved. You've had some expeditions, I believe. other people to become involved. You've had some expeditions, I believe. Indeed, and I've been so fortunate because the society has provided me the opportunity

to take a very gifted group of members to explore with us and look for evidence with about 65 million years ago, mass extinction. And we have gone actually with Walter Alvarez himself. He came and a lot of key researchers and have made some really amazing discoveries. And this actually, the members themselves were the ones who discovered a new species that had gone extinct at the boundary.

Where was the work done? The work was done in Belize. So it was a beautiful setting, extraordinarily very, very nice. The vegetation, also the wildlife. But it was quite challenging because also the heat and it was working a little bit like Indiana Jones. It was a lot of fun. I think we all came up with extraordinary growing experience.

And now the Planetary Society has its own fossil because the members of the Planetary Society were able to name this new fossil that went extinct 65 million years ago, and it's named Carthagenary Planetarius. Wonderful. You know, I had not heard that story. And that's surprising because I've heard many stories about these expeditions from the Planetary Society's fiscal person, fiscal officer, Lou Koffing,

who has accompanied you on these. And they have always sounded like one of the greatest adventures, if not the greatest adventure of her life. Yes, Lou has been an incredible enthusiast and key to these expeditions with how her we would not have been able to put

all the logistics together and so I'm very grateful to her leadership on these expeditions. With the understanding that we have only a few minutes left and we could spend an hour or two, there are a couple of other things I know we should talk about. Certainly geology, planetary

science is always going to be important to you from the sound of it. And I wonder, does that play a part in your work on the so-called Mars Express mission? Yes, indeed, because actually this planetary, the Chicxulub impact crater, which is the 65 million year mass extinction impact crater, is a great analog for Mars. It's really where, by studying the Chicxulub impact crater, we're learning a lot of what could have happened to Mars. And Mars Express, that will be launched May of 2003, is an extraordinary mission that not only has a lander, a Viggo 2,

but a very intricate set of instruments, including a radar that has never been flown to Mars before. So we're very excited by the potential science return that the mission will have. This is going to be a big year, 2003, for Mars missions, with two rovers to be launched roughly the same time by NASA. But this Mars Express is a European Space Agency mission, right? Correct, yes. It's the ESA mission to explore Mars. And actually, the European Space Agency for this year, for the 2003,

is starting with a tremendous, sweet, and ambitious set of missions, starting on the launch of January 12th of Rosetta, a mission to a comet, and then on March of 2003, SMART-1, which is a new technology mission to the moon, and then Mars Express on May of 2003. So the ESA is very busy with planetary exploration. Yes, and it's good to see, I think, here in the Global International Collaboration Scheme that more countries are getting into space planetary exploration.

This has been another major theme in your life, this idea of international cooperation in planetary and space exploration. I mean, your life itself, I think, is a good example of that. Born in Colombia, raised in Argentina, moved to the United States, studied here and now working for the ESA. You sound like you'd be a pretty good spokesperson for international cooperation. Thank you.

Thank you very much. Indeed, I think I've been so fortunate to be able to do all the things, and I want to give so much of what I have been able to receive and the kindness of all the people and agencies that I have worked and I'm working for. And one of the aspirations is that the gap between developed countries and developing countries in space exploration will become smaller and smaller. And to that effect, I've been working with the United Nations in several programs, I've been working with the United Nations in several programs, including evasive space science workshops that take place around the world to bring about this knowledge of space exploration to countries that don't have it so readily

and be able to start developing programs. And I'm very glad to mention that the United Nations has done an extraordinary effort and are continuing to do this via this workshop. The next one actually will be in 2003 in China, and last year's was in Argentina. Now, just to play devil's advocate for a moment, why is it important for a less developed country, even a third world country, why should they care about space exploration? Dreaming is something that we all have.

And it doesn't matter if you were born in a latitude that happens to fall in a developing country or a developed country. It's something that is part of human nature to explore, to learn, to know. It's something that is part of human nature to explore, to learn, to know. So knowledge is a human right that we all have and need. And to say that space exploration only belongs to developed countries is something that is really very unjust and it wouldn't be appropriate. And so I think in developing countries, you find these needs and this knowledge is something that also could help develop them in ways with the technology that could help them be

able to achieve a better standard of living for their countries. What about the issue of cooperation among nations? Of course, there have been many people, science fiction writers, Ray Bradbury among them, who have said that space offers us an opportunity to work, to dedicate ourselves to something with an intensity that is otherwise matched only by warfare. Is that something that you ever think about? affair. Is that something that you ever think about? Indeed. I think space exploration is the ultimate tool for international cooperation. It

really gives us an opportunity to work together in ways that perhaps we haven't as the civilization worked before, except perhaps in warfare. And I think the International Space Station is a wonderful example of how that can be and can happen. It's not easy. We have to learn how to do it better. But the fact is that we are starting in the past.

My dream is that someday we will go to explore the red planet as a planet with many countries participating and collaborating in unison to be able to learn to really enhance and advance the knowledge of human civilization. That is a lovely goal, and you stated very eloquently. And with that, we are out of time, I'm sorry to say. I hope that you'll join us again some other time on Planetary Radio. It will be my pleasure. And I would like to invite your audience to follow the European Space Agency's activities in planetary exploration

by going to their website, www.esa.int. Thank you. www.esa.int? you. www.esa.int Correct. Very good. Thank you very much for joining us. It was a pleasure. You bet.

We have been speaking with Adriana Ocampo, planetary scientist and a researcher for the European Space Agency and also a member of the advisory board of the Planetary Society. And we'll be back in just a moment. may have very tenuous rings made of dust blasted off its moons, Phobos and Deimos. And after the giant impact that created our moon, Earth temporarily had a ring before the moon swept up all the orbiting particles to consolidate into a single body. Maybe every planet had rings once in its history. Rings represent random, unpredictable events.

The rocky planets, with their low mass and gravity, have long exhausted their supplies of tiny moons to feed ring systems. The giant planets still have big families of small moons as players in the ring creation game. Got a question about the universe? Send it to us at planetaryradio at planetary.org, and you may hear it answered by a leading space scientist or expert. That's planetaryradio at planetary.org. Be sure to provide your name and how to pronounce it and tell us where you're from. And now, here's Matt with more Planetary Radio.

It's time for What's Up with Bruce Betts. Bruce, welcome back to the microphone. Thank you very much. What do you have for us this week? Well, first let's start with some planets that are nicely visible. Saturn comes up by the early evening in the east and is basically overhead by late in the evening. And it's a particularly great time to look at Saturn if you have a telescope, even a small telescope, because it's about as close as it gets to Earth, about as big as it will look in a telescope.

And also we're at a period where the rings are open, as opposed to looking at them edge on. I remember when Galileo saw Saturn for the first time, he thought it was like it had cup handles, I guess. And I don't know if that was the angle or the fact that he had a rather lousy telescope. There's both. There's an interesting history. When you look at diagrams from the early, very, very first astronomers looking at Saturn

because it does vary quite a lot. And so between the poor optics and the change in the ring plane, it looks very different depending on what year you're looking at it. So a good time to look at Saturn. And for this, you do need a small telescope. Binoculars might not make it. Right. If you have good binoculars and you can rest them on something,

so hold them still enough, then you might actually be able to see this. It's probably handheld is going to be a challenge unless you have really good binoculars. Or if you've got those anti-vibration electronic binoculars under the Christmas tree, maybe those will help. Well, sure. Then you're set. Some of you digress but we don't but i digress and i force you to please continue jupiter also uh very oh i should say saturn is is

uh one of the brightest objects at that time in fact the brightest in that area but there are a lot of bright stars around it um but one of the brightest objects. Look in the east. Look almost right overhead around 10, 11 p.m. Jupiter comes up in the early evening, comes up actually about an hour after sunset, and is extremely bright, brightest object in the sky at that time of night, very easy to distinguish. And then in the morning,

we still have Venus appearing in the east before dawn and the brightest object, period, in the sky at that time of night, or any time except for the sun and the moon. Speaking of Galileo, from this week in space history, on January 7, 1610, Galileo, using his telescope, discovered three of the moons of Jupiter, Io, Europa, and Callisto. This was to have quite a profound effect, besides being the first moons discovered around another body. His continuing observation of those, and then the fourth, later to be called Galilean satellite, Ganymede,

led to the thinking and the eventual proving that everything didn't revolve around the Earth, but rather in the solar system revolved around the sun, because here we could for the first time see moons revolving around another planet. And then one other thing to finish up with is just a reflection being the first planetary radio show of the new year, of what a great year it's going to be in planetary exploration. And for time's sake, we'll focus on Mars. We're going to have several launches from several countries headed to Mars, all launching in the middle of this year, and then all of them reaching the planet at the end of 2003 and the beginning of 2004.

There will actually be seven spacecraft at Mars at the end of this year, the beginning of next year. It's a traffic jam. It really is. We've got the two orbiters that are working right now from the U.S., Mars Odyssey and Mars Global Surveyor, two rovers from the United States, an orbiter from Japan, and then an orbiter combined with a lander from the European Space Agency, all getting there. In fact, because of all this excitement, as well as a couple other things happening in the planetary world at the same time, the Planetary Society will be hosting another of its well-known planet fests in the local Southern California area here

the 2nd through the 4th of January of next year to get the first live data back from the first American rover to land. So almost exactly a year from today, a planet fest for people who have not heard of it. Big, not quite a carnival atmosphere, but a pretty exciting place to be. Lots and lots of activities for young people. Should be very exciting. I'm sure we'll hear more about that as we head into the year here on Planetary Radio. Yes, we'll keep you updated. But lots of exciting things besides the live data.

There'll be speakers and panels and lots to do for adults and kids. Well, a big year in space. And, Bruce, thank you for helping us to get it off to a good start. Well, Happy New Year, Matt. Happy New Year to you, too. Bruce Betts, the Director of Projects for the Planetary Society, with What's Up, a regular feature here on Planetary Radio. That's it for Planetary Radio this week.

Join us next week for a conversation with UCI physicist and science fiction writer Greg Benford and his brother Jim. They want to prove that microwave beams can push us to the stars. Remember that you can hear this or any other edition of Planetary Radio at the Planetary Society's website, planetary.org. Have a great week, everyone. Planetary Radio is a production of the Planetary Society, which is solely responsible for its content. Our producer is Matt Kaplan. Other contributors include Charlene Anderson, Monica Lopez, and Jennifer Vaughan.

The executive producer is Dr. Louis Friedman. The opinions expressed are those of the speakers and do not necessarily reflect those of the Society or this station. Your questions and comments are always welcome. Write to planetaryradio at planetary.org. That's planetaryradio at planetary.org. Thanks for listening.